fix(subject): Fixes signature of Subject::lift

[hearnden]

Related issue (if exists):
#2539

[coveralls]

Coverage remained the same at 97.687% when pulling c6228f2 on hearnden:fix-subject-lift into ee1ce30 on ReactiveX:master.

[david-driscoll]

@hearnden thanks for the Pull Request, the change looks good to me.

We will have to discuss if it's a breaking change... honestly it could very well be a breaking change for some environments, so we'll have to decide when to bring this in.

[kwonoj]

Looks good to me. Let's discuss today's meeting for versions.

[benlesh]

@david-driscoll @kwonoj This might be breaking, so let's punt it to the next major. It's not a bug that should effect common uses cases, so we can wait a little bit.

[staltz]

LGTM

[Igorbek]

With typescript@next this signature mismatch is being caught by compiler that prevents using rxjs completely. So I would not say this is a breaking change.

[benlesh]

@Igorbek right now 6.0.0-alpha.0 is targeting TS 2.3... I'll be updating that to TS 2.4 RC in short order. That should level this out for you. However, the stable branch will stay at 2.0, as there were breaking changes required to update to 2.1. It's better to not break anyone than make a few people happy.

[karptonite]

FYI, TypeScript has released 2.4; this issue is now caught by the compiler, so it won't be possible for anyone using rxjs version 5 to upgrade to the latest TypeScript.

[david-driscoll]

Can you check if turning on skipLibCheck in your tsconfig.json will stop this error from happening? It should be a stop gap change until we can get 6.0 out.

[karptonite]

@david-driscoll Unfortunately, that doesn't help. While that gets rid of the error the compiler finds in Subject directly, it does nothing for all of the errors in my code that arise from using Subject.

[tetsuharuohzeki]

@karptonite asObservable() method might help you if your code try to assign Subject<T> to the variable/return value which expect Observable<T>.

[karptonite]

@saneyuki Thanks! I think in this case, I'm better off just staying on ts 2.3.4 until the official fix comes.

[benjamincombes]

It would be really great if it could be released as soon as possible, as it affects Angular users too that can't upgrade to TypeScipt 2.4: angular/angular#17800

[villanuevadani]

I managed to make it work with RxJS fixed at 5.4.1 and TS at 2.3.4

[OliverJAsh]

For all TypeScript users who want to upgrade to 2.4.x but don't want to use an alpha version of TypeScript, and don't want to upgrade to the next major version, is it possible to apply this change to v5 and release a new patch version? Of course this may not be possible if it's considered a breaking change.

[Igorbek]

My hack was to automatically patch rxjs typings on postinstall script to change 'lift<R>(operator: Operator<T, R>): Observable<T> to lift<R>(operator: Operator<T, R>): Observable<R>.
ps. I still cannot understand why the bugfix considered a breaking change.

[Meligy]

I also think this fix should not be considered a breaking change, and would make total sense as a bugfix release version not even minor.

[JemiloII]

This should just be a bugfix patch fix for 5.x.x. All we are doing is fixing the typings for the Typescript compiler to understand how to read and compile the code.

[fletchsod-developer]

fyi the fix already landed on RxJS 5.4.2 (changelog), you can either close this issue or leave it open.

[lock]

This thread has been automatically locked since there has not been any recent activity after it was closed. Please open a new issue for related bugs.